Antioxidants rescue murine mesangial cells from docosahexaenoic acid-induced ferroptosis.

BACKGROUND: Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are associated with anti-inflammatory effects. However, few studies have investigated their molecular effects in the kidney. We have previously shown that intrauterine growth restriction (IUGR) can lead to aggravation of mesangioproliferative glomerulonephritis and that n-3 PUFAs can attenuate long-term effects of IUGR by reversing pro-inflammatory molecular signatures in kidney cortex. RESULTS: The original aim of the study was to investigate the potential protective mechanisms of docosahexaenoic acid (DHA) on murine mesangial cells. However, stimulation with DHA alone led to reduced cell viability and ultimately cell death. Proteome analysis revealed significant regulation of ferroptosis-associated proteins. Increased expression of the pro-ferroptotic protein HMOX1 and decreased expression of the pro-ferroptotic proteins TFRC and ACSL4 could indicate the onset of self-protection mechanisms in ferroptosis that is already underway. Interestingly, treatment with the ferroptosis inhibitor ferrostatin-1 maintained cellular metabolic activity and prevented cell death, further supporting a role of ferroptosis in DHA-induced cytotoxicity. Consistently, DHA-treated cells exhibited pronounced lipid peroxidation while showing no relevant activation of apoptosis. Simultaneous treatment with DHA and an antioxidant cocktail significantly attenuated cell death and induced upregulation of several key anti-ferroptotic proteins, including TXNRD1 and GPX4, while pro-ferroptotic proteins such as TFRC and ASCL4 were further reduced. CONCLUSION: Our results provide evidence that DHA-treatment alone may have detrimental effects in susceptible cells, which could partially explain inconsistent results of clinical studies. This emphasizes the importance of a balance between pro- and anti-ferroptotic mechanisms in therapeutic strategies using n-3 PUFAs to promote kidney health.